The present invention relates to a liquid-cooled-type cooling device which is applied to, for example, a semiconductor power converter of a vehicle for cooling a heat-generating body, such as a semiconductor device.
A conventionally known liquid-cooled-type cooling device for cooling an electronic component is disclosed, for example, in United States Patent Application Laid-Open (kokai) No. 2005/0145379. The disclosed liquid-cooled-type cooling device includes a casing composed of upper and lower cover plates, and a channel plate interposed between the two cover plates and having a meandering cooling-liquid flow path and openings. Flat tubes are interposed between the two cover plates of the casing such that they are disposed in straight portions of the meandering cooling-liquid flow path of the channel plate. The upper cover plate has a cooling-liquid inlet and a cooling-liquid outlet at positions corresponding to the opposite ends of the cooling-liquid flow path. An inlet member having a coolant-liquid inflow passage which communicates with the cooling-liquid inlet and an outlet member having a coolant-liquid outflow passage which communicates with the cooling-liquid outlet are joined to an upper surface of the upper cover plate.
In the liquid-cooled-type cooling device disclosed in the above-mentioned publication, as shown FIG. 6, after hitting against a closed end surface 52 of a flow path 51 of a casing 50, cooling liquid flows upward, and flows into a cooling-liquid outflow passage 54 of an outlet member 53 via a cooling-liquid outlet 55. Therefore, when the height of the flow path 51 is high, a relatively large swirl W is generated at an internal corner portion between the lower surface of the flow path 51 and the closed end surface 52, so that flow resistance increases, and pressure loss increases.
Further, in the liquid-cooled-type cooling device disclosed in the above-mentioned publication, as shown FIG. 7, after hitting against a closed end surface 62 of a cooling-liquid inflow passage 61 of an inlet member 60, the cooling liquid flows downward while sharply changing its flow direction, and flows into a casing 64 via a cooling-liquid inlet 63. Therefore, when the cooling liquid flows into the casing 64, the cooling liquid hits the upper surface of the bottom wall 65 of the casing 64 from the upper side, whereby a relatively large swirl W1 is generated at an internal corner portion between the side wall 66 and the bottom wall 65 of the casing 64, and flow resistance and pressure loss increase.